President Obama used a magnifying glass to play a game with children at a pre-kindergarten class in an Atlanta suburb yesterday as he promoted the preschool expansion he outlined in his State of the Union Address.

Obama also gave hugs and offered fist bumps to some of the 340 kids enrolled in the infancy-to-pre-K class at College Heights Early Childhood Learning Center.

“This works,” he later told reporters after seeing education up close.

“If you’re looking for a good bang for your education buck, this is it, right here.”

Admiring the well-behaved kids, Obama said, “Playing well with others is a trait we could use more of in Washington.

“Every once in a while, have some quiet time, time-out.”

Obama proposes government funding for public preschool for any 4-year-old whose family income is 200 percent or less of the federal poverty level — a more-generous threshold than the current 130 percent threshold.